// HTMLParser Library $Name: v1_6 $ - A java-based parser for HTML
// http://sourceforge.org/projects/htmlparser
// Copyright (C) 2005 John Derrick
//
// Revision Control Information
//
// $Source: /cvsroot/htmlparser/htmlparser/src/org/htmlparser/filters/LinkStringFilter.java,v $
// $Author: derrickoswald $
// $Date: 2005/05/15 11:49:04 $
// $Revision: 1.3 $
//
// This library is free software; you can redistribute it and/or
// modify it under the terms of the GNU Lesser General Public
// License as published by the Free Software Foundation; either
// version 2.1 of the License, or (at your option) any later version.
//
// This library is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
// Lesser General Public License for more details.
//
// You should have received a copy of the GNU Lesser General Public
// License along with this library; if not, write to the Free Software
// Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
//

package org.htmlparser.filters;

import org.htmlparser.Node;
import org.htmlparser.NodeFilter;
import org.htmlparser.tags.LinkTag;

/**
 * This class accepts tags of class LinkTag that contain a link matching a given
 * pattern string. Use this filter to extract LinkTag nodes with URLs containing
 * the desired string.
 */
public class LinkStringFilter implements NodeFilter
{
	/**
	 * The pattern to search for in the link.
	 */
	protected String mPattern;

	/**
	 * Flag indicating case sensitive/insensitive search.
	 */
	protected boolean mCaseSensitive;

	/**
	 * Creates a LinkStringFilter that accepts LinkTag nodes containing a URL
	 * that matches the supplied pattern. The match is case insensitive.
	 * 
	 * @param pattern
	 *            The pattern to match.
	 */
	public LinkStringFilter(String pattern)
	{
		this(pattern, false);
	}

	/**
	 * Creates a LinkStringFilter that accepts LinkTag nodes containing a URL
	 * that matches the supplied pattern.
	 * 
	 * @param pattern
	 *            The pattern to match.
	 * @param caseSensitive
	 *            Specifies case sensitivity for the matching process.
	 */
	public LinkStringFilter(String pattern, boolean caseSensitive)
	{
		mPattern = pattern;
		mCaseSensitive = caseSensitive;
	}

	/**
	 * Accept nodes that are a LinkTag and have a URL that matches the pattern
	 * supplied in the constructor.
	 * 
	 * @param node
	 *            The node to check.
	 * @return <code>true</code> if the node is a link with the pattern.
	 */
	public boolean accept(Node node)
	{
		boolean ret;

		ret = false;
		if (LinkTag.class.isAssignableFrom(node.getClass()))
		{
			String link = ((LinkTag) node).getLink();
			if (mCaseSensitive)
			{
				if (link.indexOf(mPattern) > -1) ret = true;
			}
			else
			{
				if (link.toUpperCase().indexOf(mPattern.toUpperCase()) > -1) ret = true;
			}
		}

		return (ret);
	}
}
